1. Field of the Invention
The present invention relates to a microwave oven, and more particularly to a microwave oven having a turn table which is disposed at an inner lower portion of a cooking chamber and is driven by a motor.
2. Prior Arts
Generally, in a microwave oven, foods to be cooked are heated by microwaves generated from a magnetron. When foods received in a vessel are heated in a cooking chamber of the microwave oven, water being boiled in the vessel may overflow from the vessel to the bottom of the cooking chamber. If the overflowed water flows into a motor for driving a turn table, an electrical short of the motor can be occurred thereby causing a malfunction of the microwave oven.
In order to overcome the above problem, various types of microwave ovens are suggested. For example, a microwave oven having a drain structure is disclosed in Korea Utility Model Publication No. 94-3746. FIG. 1 shows the microwave oven disclosed in Korea Utility Model Publication No. 94-3746. As shown in FIG. 1, the conventional microwave oven 100 has a turn table 102 installed at an inner lower portion of a cooking chamber 101 and a water collecting portion 104 formed at a bottom plate 103 of cooking chamber 102. A roller assembly 105 for supporting turn table 102 against bottom plate 103 of cooking chamber 101 is provided in water collecting portion 104.
A motor bracket 106 is attached at an underside of bottom plate 103, and a motor 107 is installed at an underside of motor bracket 106. At a center of bottom plate 103, there is formed an opening 103a into which a coupler 108 for connecting turn table 102 to a motor shaft 107a is inserted. The driving force of motor 107 is transmitted to turn table 102 through coupler 108.
A motor shaft inserting hole 108a is formed at an underside of coupler 108, and an inclined portion 108b is formed at an inner circumference portion of motor shaft inserting hole 108a, as shown in FIG. 1A. In order to prevent coupler 108 from separating from bottom plate 103, a projection 108c is provided at an upper portion of coupler 108.
A bottom plate 106a of motor bracket 106 is formed at its one side with a downwardly inclined portion 106b, and a plurality of draining holes 106c is formed at an end portion of downwardly inclined portion 106b. In addition, at a center portion of the underside of motor bracket 106, there is formed an upwardly inclined portion 106d which extends into an inner portion of inclined portion 108b.
In the conventional microwave oven constructed as mentioned above, even when water W overflowed from the vessel flows along an outer surface of coupler 108, upwardly inclined portion 106d formed at the center of motor bracket 106 can prevent the overflowed water from flowing into motor 107. Overflowed water W flows along downwardly inclined portion 106b of motor bracket 106 and is draining out of microwave oven 100 through draining hole 106c.
However, conventional microwave oven 100 has no any device for draining water W remaining in water collecting portion 104, so water W, which is overflowed from the vessel and is collected in water collecting portion 104 during cooking operation, is draining toward coupler 108 only when the level of water W in water collecting portion 104 exceeds the capacity of water collecting portion 104.
That is, overflowed water W is still remaining in water collecting portion 104 if the user does not remove overflowed water W from water collecting portion 104. The remaining water is rotten as time goes by, thereby contaminating cooking chamber 101.